Merge branch 'sw/safe-create-leading-dir-race'

* sw/safe-create-leading-dir-race:
  safe_create_leading_directories: fix race that could give a false negative

sha1_file.c

@@ -124,9 +124,14 @@ int safe_create_leading_directories(char *path)
 			}
 		}
 		else if (mkdir(path, 0777)) {
+			if (errno == EEXIST &&
+			    !stat(path, &st) && S_ISDIR(st.st_mode)) {
+				; /* somebody created it since we checked */
+			} else {
 				*pos = '/';
 				return -1;
 			}
+		}
 		else if (adjust_shared_perm(path)) {
 			*pos = '/';
 			return -2;